1. Field of Invention
This invention relates to a method for manufacturing a touch panel, and more particularly to a method for manufacturing a touch panel, the method can carry out a plurality of sensor processes simultaneously.
2. Related Art
According to different principle, four types of typical touch panel are resistance type, capacitance type, sound wave type and optics type. In the past, a hand-held electronic device having small size panel includes a touch panel which is resistance type touch panel generally. However, after Apple inc. develops “iPhone” cellular phone, the capacitance type touch panel is return to be the focus of attention. According different design of a touch area, the capacitance type touch panel includes a surface capacitance type touch panel (single touch point) and a projective capacitance type touch panel (multiple touch points). The “iPhone” cellular phone uses the projective capacitance type touch panel having a function of multiple touch points, the function can detect and recognize multiple touch actions, such as narrowing/enlarging, rotating, dragging actions, etc. so as to increase the convenient during use. The projective capacitance type touch panel not only has the function of multiple touch points, but also prevents a touch screen from a wear caused by the press and pressure of fingers as compared with the conventional resistance type touch panel.
Recently, the projective capacitance type touch panel mainly includes two groups of cover glass/glass substrate and cover glass/film. Referring to FIGS. 1 and 2, Taiwan Patent No. M381836 discloses a method for manufacturing a conventional projective capacitance type touch panel. Firstly, a glass substrate 61 is provided. A silica (SiO2) is sputtered onto a surface of the glass substrate 61 so as to form a silica layer 62. An indium tin oxide (ITO) is formed on the silica layer 62 so as to form a transparent trace area 63, and a metallic layer is formed on the silica layer 62 so as to form a conductive trace layer 64. Then, an optical clear adhesive (OCA) 65 is coated on the transparent trace area 63, the conductive trace layer 64 and a region of the silica layer 62 which is not covered by the transparent trace area 63 and the conductive trace layer 64. A cover glass (tempered glass) 66 is provided, and covers the optical clear adhesive 65 by a adhesive manner, thereby bonding the tempered glass 66 to the silica layer 62 of the glass substrate 61 so as to form the projective capacitance type touch panel. The tempered glass 66 is adapted to protect the transparent trace area 63 and the conductive trace layer 64 so as to prevent the transparent trace area 63 and the conductive trace layer 64 from the environmental affect.
In order to effectively decrease the thickness, weight and material cost, the transparent trace area of the ITO layer and the conductive trace layer of the metallic layer are integrated onto the surface of the cover glass in a new process. If the strength of the cover glass is considered, a small piece of tempered glass must be used to be acted as the cover glass so as to carry out the process of the ITO layer. The prior art discloses that a small piece of tempered glass is used to carry out one sensor process on a single glass, the prior art doesn't discloses that a plurality of tempered glass are used to carry out a plurality of sensor processes on multiple glasses simultaneously. For example, the sensor process can form the ITO material, pattern the ITO layer, and form the transparent trace area by a sputtering process, a photo-resist coating process, an exposing process, a developing process, an etching process, etc.
However, one sensor process of the touch panel on a single glass will need much manpower so as to decrease the efficiency, and it is easy to touch the touch panel by worker so as affect the yield rate.
Accordingly, there exists a need for a method for manufacturing a touch panel capable of solving the above-mentioned problems.